1. Field of the Invention
This invention is in the field of medical instruments including catheters, which are particularly useful in sensing variables existing in living beings, such as the composition of blood and body fluid, contents of the digestive tract and the like, fluid pressure in a body duct and the condition of tissue, such as the lining of the digestive tract and the condition of blood vessels and their contents by visual and computer analysis.
2. The Prior Art
The prior art consists of catheters and instruments provided with light transmission and receiving means for viaually inspecting body ducts. Such devices as boroscopes and endoscopes as well as other medical instruments, have employed means, insertable into a body duct through a natural opening or incision made by a tool, for illuminating a portion of the interior of the duct and receiving light energy for providing a visual indication of the material in the duct and the duct wall to a person using such instrument.